The "tea party" is back and is brewing trouble for the Republican establishment.

After the GOP debacle in the 2012 election, when Republicans not only failed to win the presidency but blew a chance to take over the Senate, party leaders paused to consider what had gone wrong.

The Republican National Committee issued a scathing report warning that the party was in "an ideological cul-de-sac" and resolved to act friendlier toward women, minorities and low-income voters. Strategist Karl Rove said the lesson was to nominate more moderate candidates and set about raising money to do just that.

But tea party and other conservative leaders, undaunted, drew the opposite conclusion.

"It was not conservatives" who lost those Senate races, 19 of them wrote in a joint attack against Rove's efforts. "Not one moderate challenger won." The solution, they argued, was to swing further right, not toward the center.

The tea party is as fired up as ever, even though the movement is smaller now than in its heyday of 2010. In one recent poll, only 22% of American voters said they considered themselves tea party supporters, down from 30% three years ago.

But the grass-roots small-government movement has proved remarkably resilient. According to Harvard political scientist Theda Skocpol, more than 350 tea party organizations are still operating; that's roughly two-thirds of the number that sprang up in 2009 and 2010. And they have been recently reenergized by the outbreak of scandals and quasi-scandals in the Obama administration, including one that amounts to a political windfall: the discovery that the Internal Revenue Service targeted tea party groups' applications for tax-exempt status for extra scrutiny.

The approach of congressional primary elections makes the tea party a major force too. The groups have a track record of turning out in force for low-participation primaries, and adherents are an essential source for donations and volunteers in Republican campaigns.

"Tea party supporters are responsible for almost all of the total campaign activity performed by party supporters on the Republican side," a team of political scientists led by Ronald B. Rapoport of the College of William & Mary reported in a recent study. "Tea party supporters are not just a faction within the Republican Party; they are a majority faction."

The problem, of course, is that this majority faction inside the party holds views often at odds not only with a majority of all voters but with the rest of the GOP.

According to polling that Rapoport and his colleagues oversaw, 63% of tea party Republicans want to limit immigration; only 48% of non-tea party Republicans agree. Among tea party adherents, 76% want to abolish the U.S. Department of Education; only 10% of non-tea party Republicans agree.

Most strikingly, when asked whether it was more important to cut the deficit or create jobs, 63% of tea party supporters opted to cut the deficit first. Among non-tea party Republicans, the priority was reversed, with 53% putting jobs first.

That polarization already spells trouble in the House, where tea party members recently balked at "reform conservative" proposals offered by their own majority leader, Rep. Eric Cantor (R-Va.), beginning with a bill to increase funding for high-risk health insurance pools as an alternative to Obamacare. (Spending was spending, the conservatives objected; they opted for another vote to repeal Obamacare instead.)

It spells trouble in the Senate, where the tea party's newest star, Sen. Ted Cruz (R-Texas), has brought old-guard GOP leaders to the edge of rage by publicly criticizing them as "a bunch of squishes." He and other tea party senators have succeeded in blocking House-Senate budget negotiations, charging that talks might lead to a deal to raise the federal debt ceiling, which they oppose.

"I don't trust the Republicans, and I don't trust the Democrats," Cruz said.

And he's not wrong: Some Republicans do want to compromise with President Obama over the debt ceiling. In the short run, GOP leaders don't want to be blamed by the White House for touching off a financial crisis that might interrupt the economy's recovery. And in the long run, many in the GOP establishment — including House Speaker John A. Boehner (R-Ohio) — worry about being branded the party of austerity.

"That's the label President Obama is trying to put on us," said David Winston, a pollster and political strategist who has advised Boehner. "But if we become the party of austerity, then President Obama and the Democrats become the party of economic growth."

Instead of standing solely for spending cuts, Winston argued, the GOP needs to present a clearer plan for economic growth if it is to make headway in the 2014 elections. "Let's have a real discussion of what you would get with a Senate Republican majority," he told me last week. "We have to define a choice."

But tea party members aren't as worried about winning elections. According to another Rapoport survey, roughly three-fourths of tea party activists say they would prefer a strongly conservative candidate who's likely to lose over a relatively moderate candidate who's likely to win.

On paper, 2014 should be a good election for the GOP. It's the sixth year of the Obama presidency, a time when opposition parties historically do well. Democrats face an uphill battle to hold on to their 55-seat majority in the Senate. Midterm voter turnout is usually lower, so they can't count on the surge of young and minority voters who helped Obama win reelection.

But they have at least one asset: the civil war within the GOP. Once again, Democrats may prove lucky in their opponents.